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    <title>Document</title>
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<body>
    <script>
        var r = Promise.reject(20).catch(res=>{
            console.log(res);  //20
        })
        console.log(r); //Promise fulfilled
        r.catch(()=>{    //catch不能触发 
            console.log("error"); //不输出
        }).then(()=>{   //then触发
            console.log(200); //200
        })
    </script>
</body>
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